At my old job, my cubicle was right by the office of someone who always used speark phone. She came up to me once and said that she hoped that it didn't bother me, but that's just what they do in marketing. Weird. And it wasn't really annoying. It was actually interesting to be able to hear various bits of conversation otuside of my normal realm. What was more annoying was the person in the next office. She didn't use speaker phone, but I could hear her side of her phone conversations loud and clear. She liked to talk about her various medical problems to people on the phone. Really, it was just not something I wanted to hear.
That is all.